Component for pneumatic logical circuits with two distinct permission controls

ABSTRACT

A component for pneumatic logical circuits with two distinct permission controls, working with great reliability even with normal impure workshop compressed air, comprising a block with three inner chambers, wherein the chambers are separated by two elastically deformable membranes, in the first of said chambers being arranged a first passage capable of being alternately opened or closed by the said membranes, a couple of further passages entering said first chamber, all such passages being alternately connected to the feeding source, the discharge to the atmosphere, the use and the control, according to the desired logical Boolean function, and in which the other two adjacent and not communicating chambers (neither between themselves nor with the first one) serve to receive pneumatic signals in the form of input variables and acting on the said membranes, thus causing the closing and opening, respectively, of the said first passage entering the said first chamber.

United States Patent 1191 Dordoni CIRCUITS WITH TWO DISTINCT PERMISSION CONTROLS [76] Inventor: Innocente Dordoni, Strada Paullese Km. 3, Peschiera Borromeo, Italy [22] Filed: Apr. 12, 1971 [21] Appl. No.: 133,037

[30] Foreign Application Priority Data- Nov. 25, 1970 Italy 32174 A/70 [52] US. Cl l37/625.48, 137/608, 137/829, 235/201 ME [51] Int. Cl, F161: 'll/02, FlSc 3/04 [58] Field .otSeareh 137/625.48, 81.5, r 7 1 137/608; 235/201 ME [56] References Cited v UNITED STATES PATENTS 3,332,322 ,7/1967 Beck", .L 235/201 ME 3,318,329 5/1967 Norwood'.... 137/608 X 3,020,927 2/1962 McLaughlin. l37/625.48 X 3,399,697 9/1968 Schwartz 137/608 X 3,540,478 11/1970 Ito 235/201 ME 3,550,847 12/1970 Scott 235/201 MB 3,559,945 2/1971 Coiner et'al..... 235/201 ME 6/1971 Potepalov et a1. 235/201 ME Aug. 7, 1973 3,612,085 10/1971 Clark ..137/s1.sx 3,635,248 1/1972 Klee 137/815 x Prir nary Examiner-Samuel Scott Attorney-Bryan, Parmelee, Johnson & Bollinger {57] ABSTRACT A component for pneumatic logical circuits withvtwo distinct permission controls, working with great reliability even with norrnal impure workshop compressed air, comprising a block with three inner chambers, wherein the chambers are separated by two elastically deformable membranes, in the first of said chambers being arranged a first passage capable of being alternately opened or closed bythe said membranes, a couple of further passages entering said first chamber, all such passages being alternately connected to the feeding source, the discharge to the atmosphere, theuse and the control, according to the desired logical Boolean function, and in which the other two adjacent and notcommunicating chambers (neither between themselves nor with the first one) serve to receive pneumatic signals in the form of input variables and acting on 4 Claims, 4* arm-1 Figures 3' l I .2 1 gfl "11 1" COMPONENT FOR PNEUMATIC LOGICAL CIRCUITS WITH TWO DISTINCT PERMISSION CONTROLS BACKGROUND OF THE INVENTION .The present invention relates to a component for pneumatic logical circuits with two distinct permission controls acting mainly as a logical element NOR, but also adaptable to other Boolean logical functions by means of different connections to its inputs and outputs.

The component according to the invention exploits the physical principle for which a pressure signal of a still column of air is constant in all points whereas, for a flow it is relative to the upstream and downstream data of the same as well as to the configuration of the passage ducts.

SUMMARY OF THE INVENTION Therefore the main object of the present invention is that of making a bistable type memory in which, even starting from a unique feeding pressure, different states of energetic level can be created to enable the required logical circuit conditions to take place, particularly concerning the passage of air between the upstream and downstream organs of the memory.

The component according to the present invention is made up of a block identifying three chambers inside, separated by two elastically deformable membranes, in which in the first of the said chambers a first passage capable of being alternately opened or closed by the said membranes and a couple of further passages enter, all such passages being connected alternately according to the desired logical Boolean function, to the feeding source, the discharge to the atmosphere, and to the use and control, characterized by the fact that the other two adjacent and not intercommunicating chambers, (neither between themselves nor with the preceding one,) serve to receive pneumatic signals identified as input variables and acting on the said membranes, thus causing the closing and opening, respectively, of the said first passage entering the said first chamber.

Advantageously, the said two parallel membranes inside the said chambers, identify parallel pressure zones for independent control on the said first deformable membrane. In this way, interactions can be avoided between the two inputs acting on the deformable membrane and therefore the occurence of spurious return signals in the logical circuits.

The reaching of a high degree of reliability is one of the fundametal advantages of the logical element of the present invention, and allows pneumatic logical circuits to be realized in a small space and with great security, using a low pressure pneumatic system of maximum simplicity. The saving of space and economy is obvious in respect to conventional pneumatic logical circuits made up of valves and complex tubing network, which above all are not very reliable, having many moving organs formed by great masses, and the necessity of having absolute seal, very difficult to achieve because of wear on the packing.

The logical element of the present invention allows the reduction of the pneumatic logical circuits to ac ceptable proportions, and can work with great reliability even with normal impure workshop compressed air, constituting a remarkable progress even in respect to pure fluidic logical circuits,-based on the Coanda effect necessitating an extremely pure fluid, otherwise the impurities render the fluid direction uncontrollable in correspondence to the gates.

BRIEF DESCRIPTION OF THE DRAWINGS Further characteristics and advantages will appear from the detailed description of a preferred but not limiting embodiment of a logical element according to the invention, illustrated indicatively in the accompanying drawing, in which:

FIG. 1 is a cross section of such an element;

FIG. 2 shows the same component seen from above;

FIG. 3 and 4 show respectively the inner faces of the two elements or partial blocks, which are made to match and when assembled'make up the block in FIG. I.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to these figures, the component according to the invention is made upof two parts, indicated as l and 2, constituting little parallelepiped blocks preferably of molded plastic material, made to join together by means of a couple of clamping through screws 3.

Block 2, on the face towards block 1 identifies a chamber 5, of a substantially rectangular form which is prolonged laterally with an extension 6. In the centre of chamber 5 a projection 7 is obtained. Corresponding to such a projection,- a first passage 8 enters into chamber 5, which, bending at an angle inside block 2, ends in a fitting 9 for connection to the outside (atmosphere or other elements of the logical circuit). In addition on the two sides of passage 8, two further passages, respectively l0 and 11 are obtained, also connected respectively by means of fittings l2 and 13 with the outside of the block. In order to obtain the logical NOR function with this element, passage 8 is connected upstream, with a pressure source of the fluidic circuit, and passage 11 must be connected downstream with further elements of the logical circuit to be controlled, while passage 10 should simply be connected to the outisde.

Block I on the face towards block 2 has got a couple of cavities. The first cavity is assimilated by chamber 14 in a shaped outline, in the centre of which passage 15 enters, connected by fitting 16, to a constant pressure source suitable for the element controlling signal. Always on the same face of block I a further hollow or chamber 17, is obtained which does not communicate with chamber 14, and in which passage 18 enters, connected by fitting 19, to another source of controlling signals at the same energetic level.

Between blocks 1 and 2 a couple of elastically deformable membranes 20 and 21 are interposed. In FIG. I the two membranes appear slightly separated. In reality although distinct, they match together.

While membrane 20 extends over all the contact surface between blocks 1 and 2, membrane 21 shows a hole 22, in correspondance to chamber 17 and particularly passage 18. Corresponding to such a hole membrane 21 is tightened by washer 23. In this way, while passage 15 communicates with chamber 14, passage 18 communicates by hole 22 of membrane 21, with the finest interstice between membrane 21 and 20. This interstice shows in reality, a lesser thickness than that shown in FIG. 1, in which, the said interstice is marked with reference numeral 24. The membranes are preferably made of material insensitive to the impure compressed air of the factory, as for example, silicone rubber. The logical elements of the present invention, can be assembled on a panel of logical circuits as they are simple to arrange and take up little space, fixing them to the panel by means of a screw passing through hole 25 made in one of the two blocks.

The operation as logical element NOR of the component now described is the following:

Assume that initially the component is arranged as shown in FIG. 1. As such no signal comes from passages 15 and 18, so that passage 8 is open. In this condition, the pneumatic signal entering from said passage 8 branches out into passages 10 and 11 Closing passage 8, signal 11 is cut and chamber 5 discharges through passage 10. The interception of passage 8 is obtained by a pressure signal on the lower membrane 20, so that this, deforming, closes passage 8.

The signal which causes the deformation of membrane 20 can be obtained by two independent ways (or sources). A first control can come from passage 15; in this case the low pressure air flow, invading chamber 5, presses on membrane 21 and this deforms, pushing in its turn, on membrane which closes passage 8. It should be observed, that in this case the flow of air which invades chamber 14 without finding any exit, goes to affect the other sections of the component.

However, a similar interception control of passage 8 can be obtained by sending a flow through passage 18. In this case, the air going through membrane 14 in correspondance to hole 22, invades interstice 24 and, acting directly on membrane 20 (and no longer with the interposition of membrane 21), has the same effect of deforming membrane 20, making it close passage 8. At the cessation of the flow from passages 18 (or 15) the initial conditions are restored, the membranes returning to the condition shown in FIG. 1.

It is to be noted that chamber 14 is opportunely shaped, in such a way that the pressure on membrane 21 is uniformely distributed on a wide surface, avoiding on the other hand, that when pressure in chamber 14 ceases, the membrane itself can reenter, going to. adhere on the opening of passage 15 (from which detachment might some times be difficult).

Therefore, a component is obtained which, although starting from a single feeding pressure, creates, between two facing chambers which obtain parallel pressure zones, different states of energetic level permitting movement of elastic membrane 23 and the realization of the desired air conditions. Thus a control element of the gas flow has been singled out in this way, which, even working on a concept of levels, and therefore energetic equilibria, realizes a state of output levels of all or nothing, avoiding, when applies as a logical circuit element, critical working complications deriving from possible variations of the probable levels involved.

Using as output parameters the same which define the operation, the said element can satisfy the needs connected to signals with a continuous variation of energetic level (i.e. pressure).

In other words by means of the use of two membrancs a simple element has been obtained, accomplishing the Boolean logical function NOR which simplifies the realization of logical blocks even with complex functions. By connecting the outputs and inputs of the element in a different way, or using it only partially, the following other logical Boolean functions can however be carried out: YES, NOT, OR active, inhibition, AND.

The logical function YES is obtained by connecting an input control to 15 or 18, the feeding source to 10, the discharge to the atmosphere to 8 and the use to 11.

The logical function NOT is obtained by connecting an input control to 15 or 18, the feeding source to 8, the discharge to the atmosphere to 10 and the use to l 1.

The logical function OR active is obtained by connecting two input controls to 15 and 18, the feeding source to 10, the discharge to the atmosphere to 8 and the use to 11.

The logical function INHIBITION which in this system is a passive element is obtained by connecting the inhibiting signal to 8, the inhibitor signal to 15, the use to 11 and the discharge to 10.

The logical function AND, which is also a passive element in this system, is obtained by connecting the two input controls to 15 and 10, the discharge to the atmosphere to 8 and the use to 11.

Thus the advantage can be seen of having a single logical circuit element which can carry out indifferently various logical functions, with great simplifications of stocks, as well as circuit simplification because the least possible number of elements is used.

A further possibility for use of the logical element of the present invention is given by the realization of the passive function 0R, coupling two half blocks 2 together (FIG. 3), instead of a half block 1 and a half block 2, of which one block 2 is punched only in 8 and 11 (or 10.) and the other block 2 is punched only in 8, and putting only one membrane between them correspondingly punched to 1 l or 10, thus having two inputs (the two and an output (10 or 11). This further possibility is very important because the element thus conceived consumes air without loss and as the logical passive element OR is that most used in the logical circuits a great economy in consumption of feed fluid is achieved. 1

I claim:

I. A logical element for pneumatic logical circuits which is capable of response to two independent pneumatic input signals, comprising:

a block arranged with an open space therewithin;

two elastically deformable membranes disposed adjacent to one another and across the open space in theblock to separate the open space into three non-intercommunicating chambers, said three chambers comprising an inner chamber between the two membranes and two outer chambers between the block and one of the membranes;

said block having first passage means for a pneumatic signal extending into a first one of said outer chambers and being capable of being opened or closed by deformation of the adjacent membrane thereagainst;

said block having additional passage means extending to said first outer chamber which, together with said first passage means, are to be connected in a predetermined arrangement to a feeding source, to an atmospheric discharge, or to use and control conduits to obtain the desired Boolean logical function for the element; and

control passage means for supplying said two independent pneumatic input signals to the inner chamber and to the remaining outer chamber, respectively, the application of a pneumatic input signal to the inner chamber causing the closing-of the firstpassage means by deforming the membrane adjacent the first passage means, and the application of a pneumatic input signal to the remaining outer chamber causing the closing of the first passage means by deforming both of the membranes, whereby said first passage means is controlled independently by said two pneumatic input signals.

2. A logical element according to claim 1, wherein the control passage means for supplying a pneumatic input signal to the inner chamber between said membranes comprises a hole in one of the membranes and a passage in said block registering with said hole.

3. A logical element according to claim 1, characterized by the fact that the block is made up of two parts, joined by fixing and clamping the two membranes between them. I

4. A logical element for pneumatic logical circuits which is capable of response to two independent pneumatic input signals, comprising: V

a block arranged with an open s pace therewithin;

two elastically deformable membranes disposed adjacent to one another and across the open space in the block to separate the open space into three non-intercommunicating chambers, said three chambers comprising an inner chamber between the two membranes and two outer chambers between the block'and one of the membranes;

said block having first passage means for a pneumatic signal extending into a first one of said outer chambers and being capable of being opened or closed by deforming of the adjacent membrane thereagainst;

' said block having additional'passage means extend- 6 ing to said first outer chamber which, together with said first passage means, are to be connected in a predetermined arrangement'to a feeding source, to an atmospheric discharge, or to use and control conduits to obtain the desired Boolean logical function for the element; and

control passage means for supplying said two indesaid logical element being characterized by the fact that the remaining outer chamber corresponds to the passage capable of being opened and closed by the membranes, but is on the opposite side of the membranes from the first outer chamber and first passage means, has an outline arranged to provide the block with a plurality of ribs which extend into the remaining outer chamber and divide it into several interconnected portions to distribute the pressure exercised on the membranes on a wide sur face, said control passage means for the remaining outer chamber being located in said block and leading from the remaining outer chamber, said ribs functioning to prevent retraction'of the membranes into the chamber, thereby to avoid their ad hesion to the control passage means. 

1. A logical element for pneumatic logical circuits which is capable of response to two independent pneumatic input signals, comprising: a block arranged with an open space therewithin; two elastically deformable membranes disposed adjacent to one another and across the open space in the block to separate the open space into three non-intercommunicating chambers, said three chambers comprising an inner chamber between the two membranes and two outer chambers between the block and one of the membranes; said block having first passage means for a pneumatic signal extending into a first one of said outer chambers and being capable of being opened or closed by deformation of the adjacent membrane thereagainst; said block having additional passage means extending to said first outer chamber which, together with said first passage means, are to be connected in a predetermined arrangement to a feeding source, to an atmospheric discharge, or to use and control conduits to obtain the desired Boolean logical function for the element; and control passage means for supplying said two independent pneumatic input signals to the inner chamber and to the remaining outer chamber, respectively, the application of a pneumatic input signal to the inner chamber causing the closing of the first passage means by deforming the membrane adjacent the first passage means, and the application of a pneumatic input signal to the remaining outer chamber causing the closing of the first passage means by deforming both of the membranes, whereby said first passage means is controlled independently by said two pneumatic input signals.
 2. A logical element according to claim 1, wherein the control passage means for supplying a pneumatic input signal to the inner chamber between said membranes comprises a hole in one of the membranes and a passage in said block registering with said hole.
 3. A logical element according to claim 1, characterized by the fact that the block is made up of two parts, joined by fixing and clamping the two membranes between them.
 4. A logical element for pneumatic logical circuits which is capable of response to two independent pneumatic input signals, comprising: a block arranged with an open space therewithin; two eLastically deformable membranes disposed adjacent to one another and across the open space in the block to separate the open space into three non-intercommunicating chambers, said three chambers comprising an inner chamber between the two membranes and two outer chambers between the block and one of the membranes; said block having first passage means for a pneumatic signal extending into a first one of said outer chambers and being capable of being opened or closed by deforming of the adjacent membrane thereagainst; said block having additional passage means extending to said first outer chamber which, together with said first passage means, are to be connected in a predetermined arrangement to a feeding source, to an atmospheric discharge, or to use and control conduits to obtain the desired Boolean logical function for the element; and control passage means for supplying said two independent pneumatic input signals to the inner chamber and to the remaining outer chamber, respectively, the application of a pneumatic input signal to the inner chamber causing the closing of the first passage means by deforming the membranes adjacent the first passage means, and the application of a pneumatic input signal to the remaining outer chamber causing the closing of the first passage means by deforming both of the membranes, whereby said first passage means is controlled independently by said two pneumatic input signals: said logical element being characterized by the fact that the remaining outer chamber corresponds to the passage capable of being opened and closed by the membranes, but is on the opposite side of the membranes from the first outer chamber and first passage means, has an outline arranged to provide the block with a plurality of ribs which extend into the remaining outer chamber and divide it into several interconnected portions to distribute the pressure exercised on the membranes on a wide surface, said control passage means for the remaining outer chamber being located in said block and leading from the remaining outer chamber, said ribs functioning to prevent retraction of the membranes into the chamber, thereby to avoid their adhesion to the control passage means. 